Telescopic suction member for feeding sheet material

Abstract

Apparatus for handling sheet material incorporates a suction member for engaging and lifting individual sheets in order to separate and feed them. The suction member is mounted on a telescopic structure adapted to move outwardly to engage a sheet and to retract the sheet, once engaged, into a feeding position. The head of the suction member is mounted on a swivel arrangement to permit it to adapt to the plane of the sheet.

What is claimed is: 
     
       1. A telescopic suction head assembly comprising a body, a cylinder slidable longitudinally on said body, a suction head, means for freely pivotally mounting said suction head on an end of said cylinder, whereby said suction head is free to freely tilt relative to said body and free to move rectilinearly relative to said body, and body mounting means for mounting said body in pivotally adjustable relation above a fixed support member, said body mounting means allowing said body to pivot equally freely in any direction relative to said support member. 
     
     
       2. Apparatus according to claim 1 wherein said body mounting means comprises a ball and socket joint, the socket of said joint being fixed to said support member, and the ball of said joint being fixed to an end of said body. 
     
     
       3. Apparatus according to claim 2, including resilient means connected between said body and said support member for causing said body to normally assume a predetermined attitude relative to said support member. 
     
     
       4. Apparatus according to claim 3, wherein said resilient means comprises a rubber sleeve surrounding said body and interposed between said body and said support member. 
     
     
       5. Apparatus according to claim 3, wherein said support member includes a generally horizontal surface disposed adjacent said suction head when said telescopic suction head assembly is in fully retracted position, said surface having an aperture therein aligned with said cylinder and said suction head to enable said suction head to pass upwardly through said aperture to a position spaced from said surface, said resilient means causing said body to normally assume an attitude in which said cylinder is slidable in a direction normal to said surface. 
     
     
       6. Apparatus according to claim 3, wherein said resilient means causes said body normally to assume a vertical attitude in which said suction head is located at the upper extremity of said cylinder. 
     
     
       7. Apparatus according to claim 6, wherein said support member includes a horizontal surface spaced slightly above said suction head when said cylinder is in its lowermost position. 
     
     
       8. Apparatus according to claim 7, wherein said surface has an aperture to pass said suction head, said resilient means being adapted to maintain said body in a generally vertical attitude as said cylinder and said suction head are raised through said aperture in said surface, said aperture being sized to permit said body to pivot relative to said support member as said cylinder is slid downwardly on said body to its lowermost position. 
     
     
       9. For use with a machine for handling sheet material, a method of orienting said sheets with a fixed table surface comprising the steps of providing a suction head member at a position below said table surface, supporting said suction head member on a body member, selectively raising said body member and selectively raising said suction head member above said table surface into engagement with said sheet, permitting said suction head to swivel relative to said body member for establishing an air-tight relationship with said sheet, and drawing said suction head member toward said table surface. 
     
     
       10. The method according to claim 9, including the step of tilting the member on which said suction head is supported for relieving stresses in said sheet as said sheet is drawn toward said table surface. 
     
     
       11. The method according to claim 9, including the step of mounting the member on which said suction head is supported in a predetermined spatial relationship to a table having a movable suction plate. 
     
     
       12. The method according to claim 11, including the step of mounting said suction head member in fixed relation to said movable suction plate. 
     
     
       13. Apparatus for flattening a sheet relative to a fixed plane supporting surface comprising a plurality of telescopic suction means juxtaposed with said surface in alignment with the peripheral edge thereof, each of said telescopic suction means comprising a suction head, a body for supporting said suction head for free pivotal movement relative to said body, a body member, mounting means for mounting said suction head relative to said body member, selectively operable means for extending each said suction head beyond said surface into engagement with a sheet spaced therefrom, to grip said sheet, whereby said sheet may be drawn into contact with said surface, a support member, pivot means mounting said body member pivotally relative to said support member, whereby each said suction head can move laterally relative to said surface for maintaining said sheet in a flat condition relative to said surface. 
     
     
       14. Apparatus according to claim 13, wherein said body member for each of said suction heads comprises a piston and cylinder arrangement interconnected between said suction head and said support member. 
     
     
       15. Apparatus according to claim 13, including a plane member defining said plane surface, said member having a plurality of apertures in alignment with the peripheral edge of said surface, said support means being secured to said plane member to support said suction heads centrally within their respective apertures, whereby they are free to move laterally within said apertures in any direction relative to said central position as a sheet is drawn into contact with said surface. 
     
     
       16. Apparatus according to claim 13, including a plane member for defining said plane surface, said plane member having suction means for flattening said sheet against said surface. 
     
     
       17. Apparatus according to claim 13, wherein said selectively operable means comprises means for extending said body relative to said body member until said suction head engages a sheet, and then automatically drawing said sheet to said suction head and retracting said body relative to said body member. 
     
     
       18. Apparatus according to claim 13, wherein said body member comprises a hollow member adapted to have its interior connected with a source of air at reduced pressure, said body comprises a cylinder slidable on said body member, and an aperture in said body communicating between said interior and a cavity defined between said body and body member, whereby said body is extended relative to said body member when said source is connected to said interior. 
     
     
       19. Apparatus according to claim 18, including a passageway communicating from said interior to said suction head, whereby said suction head is adapted to grip a sheet when said source is connected to said interior. 
     
     
       20. Apparatus according to claim 19, wherein said passageway is smaller in cross section than said aperture. 
     
     
       21. Apparatus according to claim 18, including a flange mounted on said body member and forming a bearing surface for said cylinder, said cavity defined by said flange, the exterior surface of said body member inwardly of said flange, and the interior surface of said cylinder inwardly of said flange. 
     
     
       22. Apparatus according to claim 21, including a passageway connecting the interior of said body member to the interior of said cylinder outwardly of said flange and to said suction head, said body having a reduced cross section outwardly of said flange, whereby said cylinder is retracted relative to said body when said suction head engages a sheet, by drawing air from the interior to said cylinder outwardly of said flange.